Risk assessment is often the primary tool used by designers to evaluate and guide the treatment of safety issues associated with their design. However, workplace health and safety legislation requires that all reasonably practicable controls be incorporated into the design. Therefore, the assessment and ranking of risk, which often occurs through the selection of qualitative values for likelihood and consequence, open to uninformed interpretation and manipulation, may not be the best tool for the task.

Leading practice Safety in Design processes focus on the systematic identification of hazards early in the design followed by the selection and implementation of all reasonably practicable controls. The justification of included controls through risk assessment is not necessary. Where reasonable practicability for a particular control is uncertain, a determination may be made by evaluating whether the whole-of-life cost of the control is grossly disproportionate with the reduction in risk, where the risk is quantitively determined using statistical likelihood and consequence values.

Using this approach; risk assessment may be a useful tool at the end of the hazard treatment process for the prioritisation, communication and acceptance of hazards, but need not be the primary tool for the management of design safety.